Editing .ttxt subtitles style

[A700]

hey, guys
I've been trying to edit the Style of the .ttxt subtitles before or after muxing them with MP4 files
until now I've been able to change The font used and the font size and the color of the subtitles
yet I've no idea how I can change the Highlighting and the outline color ... the default is black which is annoying so I want no highlighting.. also I want a black outline for the subtitles.. how am I supposed to do so ?
thanks in advance

[El Heggunte]

http://gpac.wp.mines-telecom.fr/mp4box/ttxt-format-documentation/

[A700]

http://gpac.wp.mines-telecom.fr/mp4box/ttxt-format-documentation/

yeah I read that but couldn't find a solution

[A700]

I change filltextregion to yes while the back color is 0 0 0 0 but there are still black highlighting

[El Heggunte]

Now the question is, what is your chosen player using for rendering the MP4 subtitles

DirectVobSub ignores the formatting/styling specified in the TTXT stream, and therefore
it treats TTXT in the same way it treats SRT or MicroDvd SUB.
ffdshow and Mplayer do the same.

Probably only GPAC's MP4 player offers full-support for TTXT subtitles

[A700]

I use QQ player and it responds to TTXT styling [font name, color, size, highlight..etc]
anyway, I could remove the highlight by replacing the code for subtitle text in .ttxt

<TextSample sampleTime="00:01:18.494" xml: space="preserve"></TextSample>
<TextSample sampleTime="00:01:18.662" xml: space="preserve">text</TextSample>

by this code

<TextSample sampleTime="00:00:18.000" text="'text'" highlightColor="0 0 0 0">
<Highlight fromChar="3" toChar="10" />
</TextSample>

but I can't simply do that manually for all the text in one ttxt file and regarding how many ttxt files I wanna remove their highlighting
is this any application able to do that for me ?

[A700]

I figured out how to get rid of the Highlighting
now I'm trying to put a black outline/stroke/border around the text [like the image below] of .ttxt subtitles before muxing/embedding them into mp4 files with MP4Box



can anybody tell me what is the code/command for outline color.. like these codes/command
fontSize="45"
backColor="ff ff ff ff"
fontName="Serif"

or is there an application which can put that black outline around the text for me ?

[A700]

so ? no response ?